Best way to base coat with a "layer" colour

[TrawlingCleaner]

Any tips on how to base a large area on a model with a "layer" paint? My guess is to start with a. Base colour and work my way up. The colour I'm using is thousand sons blue for my eldar and it's fine for a couple of thin coats on infantry but really starts getting patchy on larger models

[Bung]

Same as for other colors on a larger area, do it with an airbrush. 

Its the best way for larger stuff getting a uniform coat.

 

Sorry, its the best tip i can give you.